India s hot climate requires greater attention to evaporative emissions. Dr. Michael Tschantz

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1 India s hot climate requires greater attention to evaporative emissions Dr. Michael Tschantz

2 Canister capacity and purge rate are key to minimizing in-use evaporative emissions - Control technology package results from emissions standard Emissions Control Purified air vents to the environment until capacity is exceeded MAJOR CLASSES OF EVAPORATIVE EMISSIONS Refueling Vapors vent to canister during parking and operation (running loss). ORVR routes refueling vapors to canister. Vapors store in canister Energy Conservation Stored vapors sent to engine when driving Diurnal Parking Running Loss

3 NMHC Emission Rates (g/km) Evaporative emissions are 4-10 times higher than exhaust NMHC emissions with Bharat VI Comparison of Exhaust and Evap NMHC Emissions In India STATUS QUO OBD Limit Cert Limit BSVI Exhaust BSVI Evap Euro 6d Evap CH6/Tier2 Evap

4 Ozone from VOCs Ozone production potential is dependent on the amount of vapor emitted and the concentration and reactivity of each vapor component The VOC/NOx ratio is important for ozone formation chemistry High VOC/NOx ratio (NOx-limited): Ozone reduced by controlling NOx Low VOC/NOx ratio (VOC-limited): Ozone reduced by controlling VOC or NOx+VOC Controlling only NOx could increase ozone

5 In April and May 2017, 64% of the days in Delhi were above the safe standard for ozone (The Times of India, June 4, 2017) -European evaporative standards were written for moderately cool European conditions not for India s hot environment Maximum Daily Temperature, C 50 MAXIMUM DAILY TEMPERATURE FOR TWENTY LARGEST CITIES IN INDIA % of diurnals exceed 35 C 40 Ahmadabad Bangalore Bhopal Bairagarh Bombay Calcutta Chennai Cochin Willindon Coimbatore Peelamedu Gwalior Hyderabad Indore Jaipur Sanganer Lucknow Amausi Nagpur Sonegaon New Delhi Patiala Patna Poona Rajkot Surat Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Day of Year

6 Secondary organic aerosol (SOA) from VOCs Volatile Organic Compound Evaporation, Combustion, Biogenic Emissions Oxidant OH NO 3 O 3 Yields Secondary Organic Aerosol Condensation New Particle Formation SOA is a significant fraction of total particulate matter (PM) mass

7 Secondary organic aerosol (SOA) from VOCs SOA production depends upon emission concentrations and atmospheric chemistry (reactivity and SOA yield) of each vapor component. Aromatic hydrocarbons are an important class of SOA precursors due to their abundance in urban environments and high SOA yields under certain conditions SOA yields in the literature range from < 5% to >38% Carter et al., 2012 The large variability in SOA yields result from a non-linear sensitivity to NOx SOA yields can increase as NOx is reduced Control strategies focused only on reducing NOx may lead to increases in SOA from VOCs

8 Bharat VI and Evaporative Controls - How do the regulatory requirements translate into in-use control? Development of evaporative standards are different from tailpipe consideration of the local climate conditions must be taken into account It is simply too hot in India for European-based evaporative controls to be effective

9 Maximum Daily Temperature, C Daily In-Use Canister Emissions (g/d) Maximum Daily Temperature, C Daily In-Use Canister Emissions (g/d) 50 Diurnal canister emissions are seven times higher with the same evaporative standard in India compared with Europe - Only by adopting US or Chinese standards can India bring diurnal emissions down to levels in Europe Daily Maximum Temp for Paris and Daily Average Canister Emissions (g/d) Across Year Daily Maximum Temp for New Delhi and Daily Average Canister Emissions (g/d) Across Year hr Std hr Std Day of Year hr Std Day of Year 24-hr Std China 6/Tier 2 ORVR + 48/72-hr -Vapor generation is exponential with temperature. -Canister capacity and purge are unable to keep up with vapor generation in India

10 Annual Evaporative Emissions (g/veh.yr) 95+% emissions reduction to Tier 2/China 6 levels at a cost of less than 2200 INR/vehicle AVERAGE LIGHT DUTY VEHICLE ANNUAL EVAPORATIVE EMISSIONS FOR INDIA AS A FUNCTION OF REGULATORY LEVEL 7000 Not Regulated in BS VI - Running losses - Refueling Marginally Regulated - Diurnal - Permeation Permeation Running Loss Hot Soak Refueling Diurnal Bharat III,IV,VI Euro 6d US Tier 2 or China 6

11 China 6 completed in December Includes ORVR, High Temp Running Loss Drive, and 48-hour Diurnal+HS using modified Type IV diurnal test and new Type VII refueling test Full national implementation by July 1, 2020 Key evaporative provisions: Onboard Refueling Vapor Recovery (ORVR) w/ 0.05 g/l limit and 0.01 g/l DF 48-hr diurnal with 0.70 g/d limit w/ 0.06 g/d DF Includes high temperature running loss drive In-use compliance testing Useful Life requirements: o China 6a: 160,000 km/12-year o China 6b: 200,000 km/12-year (7/1/23) OBDII leak detection limit of inch Utilizes WLTP drive cycles and could drop into Bharat VI seamlessly as replacement to 24-hour Type IV test Early implementation likely: Hebei Province Announced (January 2019) Guangdong Province Intending (January 2019) Shanghai region intending (January 2019)

12 Bharat VI will continue to rely upon 1982 technology to control evaporative emissions, which results in low canister capacity and low purge rates 1-Day+HS Euro 3,4,5,6a,6b Bharat III,IV,VI 2 g/day limit Standard 2 g/d limit 1982 Technology Canister Capacity* (g GWC) Average Purge Rate* (LPM) Typical Canister Emissions in SHED for Certification (g/day) Day 1 Day 2 Day 3 37 grams 2.3 LPM 0.60 g Day+HS Euro 6d UNECE GTR ~1 g/d limit 62 grams 6.9 LPM 0.10 g 0.24 g --- KLEVIII 0.35 g/d limit ORVR+ 48/72-hr+HS US Tier 2 China Technology g/d limit 108 grams 15.2 LPM 0.02 g 0.06 g 0.13 g US Tier g/d limit 2001 Technology *Based on 60-liter fuel tank 113 grams 15.2 LPM 0.001g 0.01 g 0.07 g

13 ORVR is the most effective and least costly method for refueling control Stage II Vapor Recovery Uncontrolled Refueling Onboard Refueling Vapor Recovery (ORVR) Stage II Vapor Recovery ORVR Efficiency 70% Overall 98% Overall Cost 53 Lakh Rupees/station Rupees/vehicle Maintenance 2 Lakh Rupees/year None

14 LDV Evaporative VOC Inventory (mt/year) India s VOC inventory is estimated at 150,000 mt/yr and will continue to increase with BS VI - Only means to reduce inventory with increasing vehicle population is to adopt ORVR, multiday diurnal, and running loss control - Inventory will continue increasing even if Euro 6d with 48hr diurnal is adopted TOTAL LIGHT DUTY EVAPORATIVE INVENTORY FOR INDIA 1. Status Quo (24hr Diurnal) 2. Add Euro 6d 48hr in Add ORVR+Tier 2 (China 6 equivalent) in Status Quo Euro 6d China 6 - Tier 2 Status Quo Euro 6d (48hr Diurnal) ORVR+Tier 2 (China 6) Year

15 SUMMARY 1. India s hot climate results in high year-round evaporative VOC emissions. In Europe, only 2% of days exceed 35 C, while 30% of days exceed 35 C in India. European evaporative policy-makers do not take India s hot climate into account, and European evaporative regulations should not be basis for Bharat standards. 2. While significant reductions in exhaust emissions are expected with Bharat/Euro VI, the evaporative VOC inventory will continue rising above the current level of 150,000 mt/yr unless improved norms are enacted. 3. Evaporative standards were not improved in Bharat VI, but VOCs from evaporative emissions are significant contributors to ground level ozone, SOA (PM2.5) formation, and benzene/hap exposure. 4. New China 6 standards demonstrate that ORVR, multiday diurnals, and running loss control can incorporate the WLTP, streamline for growing automotive markets, and can be quickly implemented. China is implementing with 2-3 years notice! China s evaporative program could serve as a model for India.